SDL_SetWindowBordered

#include <SDL3/SDL_video.h>

bool SDL_SetWindowBordered(SDL_Window *window, bool bordered);

This will add or remove the window's SDL_WINDOW_BORDERLESS flag and add or remove the border from the actual window. This is a no-op if the window's border already matches the requested state.

You can't change the border state of a fullscreen window.

window

the window of which to change the border state.

bordered

false to remove border, true to add border.

Returns true on success or false on failure; call SDL_GetError() for more information.

This function should only be called on the main thread.

This function is available since SDL 3.2.0.

SDL_GetWindowFlags(3)